document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=974517>Question 974517</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Verify the identity: sin4x=4sinxcosx - 8 sin^3cosx  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #598229 by </B><A HREF=/tutors/aboutme.mpl?userid=FrankM><B>FrankM(1040)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=FrankM><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=FrankM><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=598229\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> For this solution, we're going to use 2 double angle equations:\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%282x%29=2sin%28x%29cos%28x%29 ALIGN=MIDDLE  ALT=\"sin%282x%29=2sin%28x%29cos%28x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "and \r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%282x%29=1-2sin%5E2%28x%29 ALIGN=MIDDLE  ALT=\"cos%282x%29=1-2sin%5E2%28x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%284x%29=2sin%282x%29cos%282x%29 ALIGN=MIDDLE  ALT=\"sin%284x%29=2sin%282x%29cos%282x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%282sin%28x%29cos%28x%29%29%281-2sin%5E2%28x%29%29 ALIGN=MIDDLE  ALT=\"2%282sin%28x%29cos%28x%29%29%281-2sin%5E2%28x%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4sin%28x%29cos%28x%29-8sin%5E3%28x%29cos%28x%29 ALIGN=MIDDLE  ALT=\"4sin%28x%29cos%28x%29-8sin%5E3%28x%29cos%28x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "and it looks like this\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/display-illustration.mpl?tutor=FrankM&illustration_name=sin4x.png\">.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );